This invention relates to fluid flow systems, particularly to devices used in such systems to cause fluid to be pumped in a pulsatile manner. The invention is useful particularly, although not exclusively, in medical environments, such as in operating rooms, where sources of positive and vacuum pressure sources are readily available.
Various devices for causing pulsatile fluid flow have been known and have found increasing use in a variety of environments including medical and dental environments. Pulsating fluid jets are effective to remove surgical debris from a surgical site. The use of pulsating fluid jets has been demonstrated to be a very effective way of cleaning wounds or applying antibiotics, disinfectants and the like. The effectiveness of the pulsating fluid technique is the result of the repeated flexure of tissue and/or repeated dynamic impact from the pulsations which tend to materially assist in working loose of dirt particles and other debris. They are useful in orthopedic surgical procedures to clear away bone chips.
Pulsating water flow devices also have been available for some time for use in connection with dental and oral hygiene and maintenance to remove food particles from difficult to reach crevices as well as to stimulate gums and oral tissue.
In addition to use of pulsating jets, some medical and operating room techniques call for low flow, more gentle pulsatile or peristaltic pumps. For example, they can be used to draw fluids from closed wounds and to deliver the fluids to a storage receptacle. They may be used as stomach pumps. Such a device may be used to collect blood and/or to effect transfusion from a donor to a donee. Low pressure, pulsatile pumps also are useful in kidney dialysis techniques to transfer blood to and from the dialysis machine.
In general, the various pulsation flow systems which have been available utilize intermittent pumping devices of some complexity. Typically the device requires a pump mechanism which is driven by any of a variety of motors. The pump and motor systems may be electrically operated or, in some instances, may be operated in response to the fluid pressure and flow of the fluid which is to be pulsated.
While a number of devices which utilize a pulsatile flow device have enjoyed varying degrees of commercial success, they still are not free from difficulties. For example, they tend to be somewhat cumbersome and are not as portable as would be desired. When the fluid pulsatile device is used in a surgical or operating room environment, it is preferable that it be small, as compact and as light as is reasonably possible. While it would be desirable to have a prepackaged, presterilized disposable device, none has been available to date.
It is among the primary objects of the invention to provide an improved and greatly simplified fluid pulsatile device having embodiments which are operable in response to positive or negative pressure differentials.